Raman studies on nanocomposite silicon carbonitride thin film deposited by r.f. magnetron sputtering at different substrate temperatures

Raman studies of nanocomposite SiCN thin film by sputtering showed that with increase of substrate temperature from room temperature to 500 degrees C, a transition from mostly sp(2) graphitic phase to sp(3) carbon took place, which was observed from the variation of I(D)/I(G) ratio and the peak shifts. This process resulted in the growth of C(3)N(4) and Si(3)N(4) crystallites in the amorphous matrix, which led to increase in hardness (H) and modulus (E) obtained through nanoindentation. However, at a higher temperature of 600 degrees C, again an increase of sp(2) C concentration in the film was observed but the H and E values showed a decrease due to increased growth of the graphitic carbon phase. The whole process got reflected in a modified four-stage Ferrari-Robertson model of Raman spectroscopy. Copyright (C) 2010 John Wiley & Sons, Ltd.